Fire-box for locomotives



(No Model.)

M. KEARNEY & M. O. HAWLEY.

FIRE BOX FOR LOCOMOTIVES.

No. 244,392. Patented July 19; 1881.

WITNESSES:

N PEIERS, mun-01mm. WuNnglon D. C.

UNITED STATES PATENT OFFICE.

MICHAEL KEARNEY, OF NORTH SPRINGFIELD, AND MELVILLE O. HAWLEY, OF ST.LOUIS, MISSOURI.

FIRE- BOX FOR LOCOMOTIVES.

SPECIFICATION forming part of Letters Patent No. 244,892, dated July 19,1881.

Application filed June 3, 1881.

To all whom it may concern:

Be it known that we, MICHAEL KEARNEY, residing at North Springfield,Greene county, and MELVILLE O. HAWLEY, residing at St. Louis, both inthe State of Missouri, citizens of the United States,'have inventedcertain new and useful Improvements in Fire-Boxes for Locomotive andother Boilers; and we do hereby declare the following to be a full,clear, and exact description of the same, which, taken in connectionwith the drawings forming part of this specification,-will enable othersskilled in the art to which it appertains to apply the same.

Our invention relates to that class of fireboxes wherein the air forsupporting combustion, together with the gases generated from the fuel,are caused to pass downward through the incandesent fuel, whereby lossof fuel is prevented and perfect combustion is obtained, and has for itsobject to simplify the construction and increase the durability of thefire-box, as well as to obtain the greatest evaporating or heatingsurface for the boiler.

To this end it consists, mainly, in carrying the crown-sheet from therear of the fire-box downward and forward in' the arc of a circle to apoint on line with the grate, and then upward and backward in the arc ofa circle concentric with the first until-it joins the inside sheet atthe back of the fire-box, so as to form a diaphragm having a water-spacecontinuous with the boiler and its water-legs, and in combining withsaid diaphragm an independent transverse tubular grate whose waterbarscommunicate with the water-legs of the boiler, said grate beingarrangedin line with the lower extremity of the diaphragm formed by thecrown-sheet, whereby the effects of expansion and contraction due tointense heat are counteracted and greater evaporating -surface isobtained, all as will hereinafter more fully appear.

We will now proceed to describe our invention more specifically, so thatothers may apply the same.

Figure I is a longitudinal vertical section of a fire-box embodying ourinvention and illustrating the preferred form of applying the same. Fig.II is a vertical transverse section of the same on the line :10 as, Fig.I. Fig. III

(No model.)

represents a dump, which may be inserted at the rear of the grate.

Like letters refer to like parts wherever they occur.

A indicates the fire-box, and B the boiler, formed with connectingwater-legs cc and b I), and, if desired, with the bottom channel, 0, soas to entirely inclose the fire-box A and per mit the free circulationof the boiler-water around the same.

The grate is composed of a series of transverse tubular bars, at cl,arranged sufficiently far apart to give the required air-space betweenthe same, and in number sufficient to extend within a short distance ofthe front wall of the fire-box. These tubular grate-bars d connect withthe water-legs b b of the boiler, to permit the circulation of the Waterthrough the same.

e indicates the crown-sheet, which is connected at the rear of thefire-box to the sheets forming the inner wall of the water-leg,a, andextends downward and forward in the arc of a circle until it reaches apoint within ten or twelve (10 or 12) inches, more or less, of theinside surface of the front of the fire-box and on a line with thegrate-bars. Then turning to the back of the fire-box sufficiently toform a dcsirable water-space, it extends upward and backward in the arcof a circle concentric with the first until it joins the inside sheet,f, at the back of the fire-box. The edges of the crownsheet join thesheets forming the water-legs b b at the sides, so as to form a free andcontinuous water-channel from the water-legs through the loop of thecrown-sheet.

The crown-sheet maybe supported by suspension-links or stay-rods m m orin other suitable manner.

In the rear wall of the fire-box are two doors, h h, one above and theother below the grate, and through the crown-sheet is aflue, 'i, havinga damper, l, which may be operated in any suitable manner. The flue tserves for an upward draft, as well as to give access to the fines g.

In Fig. III is shown a dumping bar or plate, which may be arranged inthe position in the grate indicated by 12, Fig. I, and is pivoted sothat it can be turned to permit the free discharge of ashes, clinkers,&c.

The operation of the devices will be the same as is common to this classof gratesthat is to say, the fire may be started with the upward draftby opening the door h below the grate and the damper Z in thecrown-sheet, and the products of combustion will then pass directly tothe boiler-tubes 9 through the flue i. As soon as the fire is fairlystarted the damper or valve 1 of the crown-sheet and the door h can beclosed and the upper door, h, opened. This reverses the draft or causesthe air to support combustion to pass down through the fuel, carryingwith it through the incandescent fuel all gases generated from the fuel,thus insuring complete combustion and utilizing the gases, &c., whichare lost when the upward draft is employed.

At any time the fires may be damped by opening the valve or damper l andpermitting the draft from the upper door to pass directly over the fuelinto the boiler-tubes 9.

Among the advantages obtained are the combined advantages of all thebest constructions of downward draft-via, the fullhea-tin g value of thefuel is obtained, no combustible gases are permitted to escapeuuconsumed, a greater degree of heat is obtained, and slack or fine fuelcan be readily used; but owing to our method of constructing thefire-box we obtain additional advantages peculiar to our invention-viz.,the crown-sheet which divides the fire-box is continuous throughout withthe sheets forming the side walls and top of the fire-box, consequentlythe plates are free to a certain extent to spring oryield under theexpansion and contraction due to the intense heat, and thus prevent orcounteract any buckling ot' the plates, which would tend to destroy thesame, and, the water-spaces of the boiler and crown-sheet beingcontinuous, the crownsheet (or diaphragm) is fully protected by thecirculation of the boilerwater, and a more extensive heating orevaporating surface is obtained.

We are aware that fire-boxes have heretofore been constructed so as toobtain an upward draft for starting the fire and a downward draft tocarry the gases developed through the incandescent fuel, and do notherein claim the same. We are also aware that water-bars,

water-legs continuous with the boiler-sheets, and independent diaphragmsformed with water-spaces connecting by tubes with the boiler have eachand all entered into the construction of fire-boxes, and consequently donot herein claim such devices; but,

Having thus fully described our invention and indicated thedistinguishing features thereof, what we claim, and desire to secure byLetters Patent, is-

1. In a fire-box for boilers, a crown-sheet which extends downward andforward from the rear wall of the fire-box and backward and upward inthe arcs of two concentric circles, said crown-sheet being continuouswith the walls of the fire-box, and the water-space formed thereby beingcontinuous with the water-space of the boiler and its water-legs, incombination with an independent watergrate composed of transversetubular bars which communicate with the water-legs of the boiler,substantially as and for the purpose specified.

2. In a fire box for boilers, a crown sheet which extends downward andforward, then upward and backward in the arcs of two concentric circlesto divide the fire box into a fuel-chamber and an expansion-chamber, theplates of said crown-sheet being continuous with the walls of thefire-box, and the waterspace formed thereby being continuous with theboiler and its water-legs, said crown-sheet provided with a valved fluefor upward draft, in combination with tubular grate-bars arranged inline with the lower part of the curved crown-sheet and connecting withthe water-legs of the boiler and the upper and lower draft-doors,substantially as and for the purpose specified.

In testimony whereof we affix our signatures in presence of twowitnesses this 30th day of May, 1881.

MICHAEL KEARNEY. M ELVILLE C. HAW'LEY.

Witnesses E. G. OHADWIGK, W. L. CoYLE.

